Sanitary Assessment of Viral Diseases Infecting Figs in Northern West Bank -Palestine

The available data about the sanitary status of crops in Palestine is scarce, due to the lack of diagnostic facilities and equipment, for diseases, lack of specialized technicians, scientists and poor organization of nurseries and farming activities. Fig (Ficus carica) is one of the old and the most common fruit tree grown in all the Mediterranean countries, which is among those exposed to diseases and pathogens. Recent investigation indicated that fig mosaic disease was the main pathogenic agent. In this study, field surveys were conducted in the areas of northern region of West Bank- Palestine (Jenin, Tulkarem, Qalqilya, Nablus, Tubas, Salfit and Ramallah) for symptom observation during the two growing seasons of 2014 and 2015. In addition to that, a total of 50 fig samples were collected from the surveyed areas: Jenin (12), Nablus (16), Ramallah (5), Qalqilya (12) and Tulkarem (5 samples), to detect any of Fig mosaic virus (FMV), Fig badnavirus-1 (FBV-1), Fig cryptic virus (FCV), and Fig mild mottle-associated virus (FMMaV) by using RT-PCR with sets of specific primers. During the field surveys almost two third of visually inspected trees demonstrated one or more of viral symptoms. The symptoms appeared on leaves as well as fruits. The symptoms on leaves were reported as mosaic, mottling; yellowing and deformation. Surprisingly the symptoms appeared on newly growing leaves, and asymmetrically on trees, suggested the uneven distribution of the virus on the plant. Notably, mite infestations were found on some of those trees inspected as symptomatic, which may indicate they play a role as putative transmissible agents to the virus. Moreover, newly formed figs, were exhibiting yellow ring spots varied in size and strength, explaining the systematic paths of the viral infections and leading to believe of the virus existence and transmissibility within the propagated materials. Necrotic spots were also noticed on infected fig fruit. Molecularly, by using RT-PCR, all inspected viruses except of FMMaV, were detected in tested samples, with overall incidence of (78%). The most spread virus was FMV (60%) followed by FBV-1 (46%). Also were detected about 30% of mixed infection between FMV and FBV-1. Portions of the FMV and FBV genomes were sequenced and showed high similarity with published ones in GenBanks (98-100%). This study is reporting the deterioration of the sanitary status of figs in northern region of West Bank, as indicating by the high incidence of virus- infections in fig yards planted and growing there for many years. This could be considered alarming to fig production and extension in the country due to significant losses caused by the virus. As this study offered insight on the sanitary status of fig in the country, it is also highly recommended to use and produce of healthy fig seedlings and propagating materials. Key words: fig viruses, RT-PCR, Ficus carica, FMD.